There is no point in changing the color of the indent guides as it is now. The white design is neat. I would suggest to make a third option, which would combine both and profit from the changed color.

draw_normal : draws every indentation guide in whitedraw_active: same as now, but in same color as draw_normaldraw_combined: combines draw_normal with white lines and draw_active with red lines.

This way we are still able to see the indentation levels clearly, but also and most importantly, when you are searching for matching elements, you don't need to keep track on a particular guide line any more. Yaay!